Improvement in apparatus for introducing powdered fuel into furnaces



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A um@ G. K. STEVENSON.

APPARATUS Fo; INTRODUCING PownERED FUEL INTO FURNACES.

Patented Dec Iliff! f YII'I'IIESSES z TME GRAPHIC C0.N.

errer:

GEORGE K. STEVENSON, OF VALPARAISO, CHILI.

IMPROVEMENT IN APPARATUS FOR INTRODUCING POWDERED FUEL INTO FURNACES.

Specification forming part of Letters Patent N o. [$5,592. datedDecember 19, 1876; application filed September 30, 1876.

To all whom it may concern:

Be it known that I, GEORGE K. STEVEN- SON, of' Valparaiso, in theRepublic of Chili, have invented a new and Improved Apparatus forIntroducing Powdered Fuel into Furnaces, of which the following is aspecification:

The accompanying drawing represents a vertical longitudinal section ofmy improved apparatus for feeding powdered fuel to furnaces.

The object of this invention is to introduce powdered or granular fuel,such as coal, coke, or similar hydrocarbons, to furnaces adapted theretoin such a manner as to insure a more perfect combustion and moreinten-se heat than heretofore.

The invention consists in connecting the fuel-tube with furnace by asleeve and tube, the latter of which is provided with a twisted platethat is made adjustable, as hereinafter described.

The fan heretofore used exclusively in the attempts to introducepowdered fuels has not given satisfactory results, on account of theuncertainty of the blast of the fan, except at a given high velocity,which circumstance has been the cause of either their failure or ofgreatly diminished value.

The invention consists of an apparatus in which the powdered fuel ismixed with air by a suitable pressure-blower, and injected into afurnace adapted thereto, so that the coald'ust and air shall be broughtas nearly as possible to a perfect combustion, and produce gas of thegreatest effect.

rEhe apparatus may be applied to steamboilers in use without requiringany alteration, but it may also be applied to smeltirig` and otherfurnaces in convenient manner.

The apparatus is made so as to be easily removed from the mouth of thefurnace, and quickly replaced again when required, occupying but smallspace in the usually limited lire-room of marine and other boilers.

By reference to the drawing, A represents a rotary pressure-blower ofany approved construction, whose exit side is connected to a tube, B,which may be of any suitable or required section, the air being forcedby the blower through this tube into the furnace.

under a delivery-cylinder, C, which is working in proper bearings on,and partly within, the tube B, and rotated in the direction of the airfrom the blower, by suitable gearing adapted to the proportions ot' fueland speed ofthe same. The cylinder C is specially constructed to insurethe accuracy of the delivery of the powdered fuel, being arranged withina box or casing, D, and fitted into the same, so as to be practicallyair-tight therein. The cylinder C is made with cuttings or recesses of Uor other shape, and provided with clearer pins or teeth a, which work byedges or lianges in an eccentric groove at each side ofthe box D. Theclearer-pins are thereby drawn to the inside of the cylinder at theupper part, and forced toward the circumference of the same at the lowerpart of the cylinder.

The coal or other powdered fuel is fed in any suitable manner by a Atopfeed-tube and Archimedeau screw, hopper, or otherwise, to the verticalfeed-tube E, filling by the force of gravity the-spaces in the cylinder,and being carried by the revolving of the cylinder into the tube B,where the fuel is forced out by the clearer-pins and deposited in thetube B. The fuel cannot clog in the cylinder, even if it were moist orwet, as the clearer-pins will effectuall y discharge the fuel from therecesses of the cylinder.

Another advantage of the cylinder C is, that there will be no air escapef'rom tube B to the feed-tube E, as the side feeding is filled withpowdered fuel, and as the teeth ll the space on the return to receivethe charge. As the revolutions of the cylinder are necessarily slow,there will be little wear to the same. The coal or powdered fuel thusregularly fed into the tube B is, by the air from the blower, driventhrough tube B, sleeve F, and discharge-tube G into the furnace, thefuel and air being well mixed during their passage through tube B. Thesleeve F slides outube B, and is kept thereon by a collar or flange atthe end of tube, the sleeve F being tightly secured to thc collar byright-and-left-hand expansion-screws b from box D or raised parts on thetube B. The discbargetube G is made with a liange on one end, which isretained in airJtight connection with the sleeve F, by

In its passage through the tube the air passes l hook-bolts withthumb-nuts. The dischargetube may be provided with a central twisteddivision-plate, if desired, by means ot' which the fuel is thrown by awhirling movement into the furnace, and by adjusting. the tube G andtwisted plate, the direction of the fuel may be altered, as required.Any suitable spiral grinding device may be employed for giving thecurrent the whirling movement.

The parts of the apparatus are geared in suitable manner, and secured toor on a table or frame-work, which, in its turn, is supported on castersor wheels for stationary furnaces, and by horizontal screws H secured tothe door of lthe reroom, so that the whole apparatns can be moved awayfrom the furnace connection and placed into any suitable position.

In case several boilers, as in marine boilers, are used, each boilershould be supplied by one blower, the sleeve `F being made with adischarge-tube, properly gaged to equally divide the injected fuel andkair to each openin g, care being taken that the discharge-tubes are inline with the ccnterof the furnace.

Having thus described my invention, I claim as new and desire to secureby `Letters Patentl The combination, with blower A and tube B, of thesleeve F and tube G, the latter being adjustable, and provided with atwisted internal plate, substantially as and for the purpose specified.

GEORGE K. STEVENSON. Witnesses:

PAUL GOEPEL, G. SEDGWICK.

